CPCS Safe Lifting Operations & LOLER 3 — Questions and Answers
Question 1: What is the purpose of a crane load chart?
- It shows the maximum load the crane can safely lift at different radii and boom angles (Correct answer)
- It records the loads lifted during a shift
- It shows the crane's fuel consumption at different loads
- It certifies the crane for use on the site
Correct answer: It shows the maximum load the crane can safely lift at different radii and boom angles
A load chart shows the crane's capacity at different radii (distances from centre of rotation) and boom configurations. Operators must always check the load chart to ensure the planned lift is within capacity.
Question 2: What is 'two-blocking' in crane operation and why is it dangerous?
- When the load block is raised until it contacts the boom tip, which can cause wire rope or component failure (Correct answer)
- When two cranes lift the same load simultaneously
- When a load is lifted twice in the same lift plan
- When the crane operates in two separate stages
Correct answer: When the load block is raised until it contacts the boom tip, which can cause wire rope or component failure
Two-blocking occurs when the upper and lower load blocks come together, preventing further movement. Continuing to hoist causes extreme stress, potentially snapping the wire rope and dropping the load.
Question 3: Before a crane lift, wind speed should be checked. At what approximate wind speed should most mobile crane operations be stopped?
- When wind speed exceeds the manufacturer's specified limit, typically around 45-65 km/h depending on crane and load (Correct answer)
- Wind speed has no effect on crane operations
- Only when gusts exceed 100 km/h
- Wind limits apply only to tower cranes
Correct answer: When wind speed exceeds the manufacturer's specified limit, typically around 45-65 km/h depending on crane and load
Most crane manufacturers specify a maximum wind speed for safe operation. This varies but is typically around 45-65 km/h. Operators must check the manufacturer's specification and stop operations when this is exceeded.
Question 4: What does LOLER require regarding the competence of the appointed person for a lifting operation?
- They must be competent in planning and supervising lifting operations (Correct answer)
- They must hold a crane operator's licence
- They must be employed directly by the principal contractor
- They only need to be a CPCS card holder
Correct answer: They must be competent in planning and supervising lifting operations
The appointed person must be competent specifically in planning and supervising lifting operations. This is a separate competence from operating a crane and requires specialist knowledge.
Question 5: What is a 'dynamic lift' and how does it affect the SWL?
- A lift where the load is in motion (e.g. slewing with a load) — dynamic forces can reduce the effective SWL (Correct answer)
- A lift carried out at night in low-visibility conditions
- A lift where two cranes share the load
- A lift where the load is placed immediately without pausing
Correct answer: A lift where the load is in motion (e.g. slewing with a load) — dynamic forces can reduce the effective SWL
Dynamic lifts involve movement forces that add to the static load. Most crane SWLs are based on static conditions. Dynamic loading — especially during slewing or sudden stops — can significantly increase stress on the crane and accessories.
Question 6: What is the function of an anti-two-block device on a crane?
- It stops the hoist automatically before two-blocking occurs, preventing rope failure (Correct answer)
- It measures the load weight and displays it to the operator
- It prevents the crane from travelling with a suspended load
- It locks the boom at a safe angle during transport
Correct answer: It stops the hoist automatically before two-blocking occurs, preventing rope failure
An anti-two-block device detects when the blocks are approaching contact and automatically cuts the hoist function, preventing the catastrophic failure caused by two-blocking.
CPCS Safe Lifting Operations & LOLER 3
What is the purpose of a crane load chart?